With time running out for a framework Israeli-Palestiniandeal to salvage a troubled U.S.-brokered peace process, Obamaand Netanyahu sparred in public comments in the run-up to ameeting that will also focus on Iran's nuclear program.

Netanyahu arrived in Washington to a veiled warning fromObama that he would tell the Israeli leader the United Stateswould find it harder to defend Israel against efforts to isolateit internationally if peace efforts failed.

Boarding his flight to the U.S. capital, Netanyahu, who hashad a strained relationship with Obama, said that Israel knewhow to resist pressure and that he intended to stand firm onwhat he termed his country's "vital interests."

Secretary of State John Kerry has been trying to persuadeNetanyahu and Palestinian President Mahmoud Abbas to agree to aframework deal that would enable troubled land-for-peacenegotiations to continue beyond an April target date for a finalaccord. Abbas is due at the White House on March 17.

"When I have a conversation with Bibi, that's the essence ofmy conversation: If not now, when? And if not you, Mr. PrimeMinister, then who? How does this get resolved?," Obama, usingNetanyahu's nickname and borrowing from the Jewish rabbinicalsage Hillel, said in an interview with Bloomberg View.

Palestinians seek to establish a state in the occupied WestBank and the Gaza Strip, with East Jerusalem as its capital.Israel captured those areas in the 1967 Middle East war and in2005 pulled out of the Gaza Strip, now run by Hamas Islamistopposed to Abbas's peace efforts.

RECOGNITION

Israeli officials say the ball is in Abbas's court, notinghis refusal so far to agree to a key Netanyahu demand:Palestinian recognition of Israel as the nation-state of theJewish people.

Netanyahu is likely to repeat that condition in a policyspeech on Tuesday to the pro-Israel lobbying group AIPAC, atraditional podium for some of his most strident speeches.

Palestinians, who point to Israeli settlement-building inoccupied territory as an obstacle to peace, say they havealready recognised the state of Israel, through officialdeclarations and interim peace deals.

"We are working very close, very intensely with Kerry to tryto make this process work," a senior Israeli official said.

The official declined to go into detail about thenegotiations, which have been held under a virtual newsblackout, but he said Israel was ready to show flexibility,noting that Netanyahu had already described a future Kerry paperas an American document.

That could give Netanyahu - and Abbas - leeway to registerreservations that could keep political opponents of a deal atbay.

U.S. officials hope for at least modest progress but do notforesee a breakthrough in the Oval Office meeting, whichNetanyahu will follow with talks with Congressional leaders.

"If the president is able to sort of narrow gaps and getcloser to where both parties support the ideas and theframework," a senior administration official said, "then thatwould be great."

But the official added, "It's not like this is going to beanother Camp David 2000 ... I wouldn't expect majorannouncements about the future of the peace negotiations."

While the Palestinian issue and Western powers' nucleartalks with Iran are expected to dominate the Netanyahu-Obamameeting, the Israeli leader's visit is likely to be overshadowedby the crisis in Ukraine.

Obama spent much of the weekend scrambling to ease thesituation, including a long phone call with Russian PresidentVladimir Putin in which the U.S. president warned of economicand political isolation if Moscow did not withdraw its troopsfrom Ukraine's Crimea region.

On the Iranian issue, there is little expectation on eitherside that the leaders will be able to bridge their fundamentaldifferences.

Netanyahu, whose country is widely believed to be the MiddleEast's only nuclear-armed nation, denounced as a "historicmistake" an interim deal that world powers reached with Iran inNovember under which it agreed to curb sensitive nuclearactivities in return for limited sanctions relief.

He has demanded that any final deal completely dismantleTehran's uranium enrichment centrifuges, a position at odds withObama's suggestion that Iran, which says its nuclear programmeis peaceful, could be allowed to enrich on a limited basis forcivilian purposes.

"They're not going to have a meeting of the minds on this,"said Daniel Kurtzer, a former U.S. ambassador to Israel.